Conventional peanut butter is prepared from shelled peanuts roasted at about 170.degree. C. which are thereafter cooled to about 30.degree. C. These roasted peanuts are then blanched, the skins and nibs are removed and the blanched kernels are split into halves. The blanched, split peanuts are then coarsely ground and to the coarsely ground nuts are added optional ingredients, such as sweetener, salt and hydrogenated vegetable oil. All of the ingredients are thoroughly mixed and are then finely ground. This mixture is then cooled and packed into jars.
Peanut butter is a highly nutritious food containing high levels of protein. However, peanut butter also contains relatively large quantities of fat. A typical peanut butter product will have an oil content of about 50%, a protein content of about 29% and a fiber content of 1 to 2%. Sugars, carbohydrates and moisture normally constitute the rest of the product. The moisture level is usually less than about 2%. Due to the low moisture level and the high level of oil, peanut butter is a highly stable product which can be kept unrefrigerated for substantial periods of time.
To be labeled "peanut butter" under the applicable regulations of the United States Food and Drug Administration, the peanut ingredients must comprise at least 90% of the weight of the finished product, 21 C.F.R. .sctn.164.150. If more than 10% of the peanut product consists of non-peanut ingredients, then the product may be termed a "peanut spread", 21 C.F.R. .sctn.102.23(a) so long as it meets all of the conditions set forth in 21 C.F.R. .sctn.102.23(b). One of these conditions is that the protein content of the product is at least 24% by weight of the finished product.
There has been a substantial amount of research directed to reducing the oil content and, thus, the calorie content of peanut butter. One of the most common methods for effectively decreasing the amount of calories per unit volume in food products is the addition of water as a non-calorie ingredient together with a thickener or emulsifier to duplicate the texture of the original product. However, the addition of water adversely affects the flavor, color, texture and mouthfeel of peanut butter products. More importantly, unlike peanut butter which is microbiologically stable at room temperature because of the high level of oil and the low level of water, generally about 1-2% by weight, peanut butter products having high levels of water must usually be refrigerated after opening even if the peanut butter products contain preservatives to retard spoilage.
Replacement of oil with bulking agents has been proposed. U.S. Pat. No. 4,814,195 to Yokoama, et al. is directed to a reduced calorie peanut butter product containing from about 15% to about 40% by weight of a solid bulking agent selected from polydextrose and microcrystalline cellulose.
U.S. Pat. No. 4,828,868 to Lasden, et al. is directed to a low calorie, low fat peanut butter-like product and a method for making the product. In the method, unroasted defatted or partially defatted peanut flour having no more than about 35% fat by weight is milled in the presence of water to a maximum particle size of about 150 microns. The mixture of water and peanut flour is then cooked at a temperature of between about 175.degree. F. and the boiling point of the mixture of peanut flour and water. The moisture level of the finished product is high and it is indicated in the Lasden, et al. patent that the product requires refrigeration for extended shelf life. While the Lasden, et al. patent indicates that defatted peanut flours that have as little as 1% fat can be used, no specific examples are provided as to how to produce a peanut butter product having as low as 1% fat.
It would be highly desirable to provide a flexible method for preparation of lowered fat peanut butter products having from about 50% to less than 1% of the fat normally associated with peanut butter, i.e., a total fat content of from about 1% to about 25%.
Accordingly, it is a principal object of the present invention to provide a method for the manufacture of lowered fat, high moisture peanut butter products.
It is another object of the present invention to provide high moisture, lowered fat peanut butter products which are shelf stable without refrigeration.